Bioenergetics

Question 1

What is photosynthesis

Answer 1

Photosynthesis is the process in which plants make glucose from sunlight. It is an endothermic reaction in which energy is transferred from the enviro to the cholera blast by light.

Question 2

Photosynthesis equation

Answer 2

carbon dioxide + water -> glucose + oxygen

Question 3

Rate of PS temperature

Answer 3

Which increase in temp the rate of ps increases. As the reaction is controlled by enzymes this trend continues up to a certain temp until the enzymes begin to denature and rate of reaction decreases.

Question 4

Rate of PS Light

Answer 4

Higher light = more rate of reaction until it becomes a limiting factor

Question 5

Rate of PS C02 concentration

Answer 5

Higher concentration = higher rate

Question 6

Rate of PS chlorophyll

Answer 6

Pigment within the leaf that converts light energy to food for the plant therefore it is essential. if chlorophyll levels were decreased through magnesium deficiency, then the rate of photosynthesis would decrease.

Question 7

Experiment to measure oxygen production

Answer 7

• Pondweed is placed into a test tube filled with water.
• lamp is placed at a measured distance from test tube
• The rate the bubbles coming out of the pondweed shows how much the plant is breathing/synthesising due to the light.

Question 8

Limiting factors

Answer 8

environmental condition which, in lo levels, restricts any increase in the rate of photosynthesis. Despite increases in other factors the rate of photosynthesis can no longer increase. this is evident in a graph levelling off.

Question 9

Inverse proportion

Answer 9

The relationship between two factors which involves one increasing while one is decreasing. As the distance between the light source and the plant increases the light intensity decreases. - Inverse square law

Question 10

Uses for glucose

Answer 10

• Respiration
• converted to insoluble starch ( roots, stems and leaves )
• Produce fat or oil for storage
• Produce cellulose
• Combine nitrates to form amino acids which produce proteins.

Question 11

Aerobic respiration equation

Answer 11

C6h12O6 + O2 —> CO2 + H2O

Question 12

Aerobic respiration

Answer 12

Use of oxygen
yields most energy and is mainly occurs in the mitochondria

Question 13

Anaerobic respiration

Answer 13

• Occurs when there is not enough oxygen
• Does not create that much energy and only lasts for a short period of time.

Question 14

Anaerobic respiration ( animals )

Answer 14

Glucose —> lactic acid

Question 15

Anaerobic respiration ( Plant / yeast cells )

Answer 15

Glucose—> Ethanol + Carbon dioxide

Question 16

When respiration rate increases how does more oxygen get supplied

Answer 16

-Heart rate increasing
-Breath rate increasing
-Breath volume increasing

Question 17

What’s is oxygen debt

Answer 17

Oxygen debt is the extra amount the body needs after exercise to react with the accumulated lactic acid and remove it from the cells, this results to muscle tiring and not contracting properly.
- Blood flowing by the muscles will carry the lactic acid to the liver where it will be converted back into glucose.

Question 18

Metabolism

Answer 18

The reaction of all the reactions in a cell or the body. The energy transferred in the cells by respiration is used in the process of metabolism to make new molecules. These processes are controlled by enzymes.

Question 19

Examples of metabolic reactions

Answer 19

Glucose molecules being converted to starch, glycogen and cellulose by being joined together.
Glycerol molecule and three molecules of fatty acids forming a lipid molecule
Reaction in respiration.

Question 20

Structure of a leaf

Answer 20

Cuticle - Waxy layer prevent water loss (transparent)
Upper epidermis - Protective layer / produces cuticle
Palisade Mesophyll - Rod shared cell containing chloroplasts for PS. At to for max light. Upright and elongated / packed closely together.
Spongy mesophyll - Have large airspace to allow CO2 and O to diffuse around. Large Surface area to maximise this.
Vien - containing xylem ( carry water ) and Phloem ( vessels that carry dissolved nutrients )
Lower epidermis - protective layer. contains stomata that allow CO2 and O to move in and out.
Stomata - surrounded by guard cells. open = hot / water vapour
Close = prevent water loss.

Question 21

Uses of energy released in respiration

Answer 21

Keeping warm
Active transport
Building larger molecules
Movement